1. Technical Field
The present disclosure relates to a turbocharger including a seal plate which is provided opposed to a back surface side of a compressor wheel.
2. Description of the Related Art
There has heretofore been known a turbocharger in which a shaft provided with a turbine wheel on one end and a compressor wheel on the other end is rotatably supported by a bearing provided in a bearing housing. The turbocharger thus configured is connected to an engine, then the turbine wheel is rotated by exhaust gas discharged from the engine and the compressor wheel is rotated through the shaft by the rotation of the turbine wheel. Thus, the turbocharger compresses air along with the rotation of the compressor wheel and sends the compressed air out to the engine.
In a turbocharger shown in Japanese Patent Application Laid-Open Publication No. 2005-76463, for example, a seal plate opposed to a compressor wheel is provided on a back surface side of the compressor wheel (i.e., on a side facing a bearing housing when viewed from the compressor wheel). The seal plate is fitted and fixed into a hole formed in a bearing housing, and prevents lubricant oil having lubricated a bearing from leaking out of the bearing housing to the compressor wheel side. Moreover, a diffuser flow passage is formed on outside in a radial direction of the seal plate. The diffuser flow passage is formed annularly by using mutually opposed surfaces of the bearing housing and a compressor housing, the surfaces being provided with a space in between. Air is compressed by the compressor wheel and then flows in the diffuser flow passage outward in the radial direction.